SANAA, YEMEN -- Yemeni security forces killed an al-Qaeda leader during clashes in an extremist stronghold while a road ambush by militants left two soldiers dead Wednesday in the latest battles in an escalating war.

Soldiers surrounded the home of al-Qaeda cell leader Abdullah al-Mehdarhad in the Habban region of Shabwa province in Yemen's southeast. That triggered a shootout in which Mehdarhad was killed, according to 26Sep.net, a Yemeni Web site that serves as a mouthpiece of the nation's military.

Meanwhile, Mehdarhad's followers ambushed a Yemeni military unit on a nearby road, killing two soldiers. The attack was thought to be an attempt to draw soldiers away from the siege, the Web site reported. Four suspected militants were arrested.

Wednesday's operation was the latest in a series of strikes against suspected al-Qaeda fighters conducted by Yemen's government, with U.S. assistance, in the wake of the attempt to bomb an American airliner on Christmas Day. Yemen, the Arab world's poorest nation, is under immense U.S. pressure to combat al-Qaeda in the Arabian Peninsula, which has asserted responsibility for the airliner plot. At the same time, the government increasingly views the Yemen-based al-Qaeda affiliate as an internal threat, not just a problem for the West.

Since the failed bombing, the United States has doubled its counterterrorism funding and training, as well as increased its economic aid.

The intensified campaign against al-Qaeda comes as Yemen's government seeks even more economic and development aid to combat extreme levels of poverty, unemployment and illiteracy. World leaders are scheduled to meet in London on Jan. 28 to discuss ways to combat Islamic radicalization in Yemen. The government is besieged with multiple emergencies, including a civil war in the north and a secessionist movement in the south. Even as the government takes on al-Qaeda, its five-month-old offensive against Shiite rebels in the north is intensifying.

Yemeni Interior Ministry officials said Wednesday that at least 15 rebels were killed in clashes over the past two days; a day earlier, a Saudi defense official said the kingdom's forces had killed hundreds of Yemeni rebels inside Saudi territory, an assertion that could not be independently verified. Saudi Arabia entered the conflict in November after a Yemeni rebel raid into its territory.

Saudi Arabia's assistant defense minister, Prince Khaled bin Sultan, told reporters that clashes with the Yemeni rebels have killed 82 Saudi soldiers, underscoring the toll the kingdom is enduring even as it conducts airstrikes and uses heavy firepower against the rebels.

On Wednesday, Iranian President Mahmoud Ahmadinejad criticized Saudi Arabia's role in the conflict. "We were expecting that Saudi Arabian officials act like a mentor and make peace between brothers, not that they themselves enter the war and use bombs, cannons and machine guns against Muslims," Ahmadinejad said in a televised speech.

Yemen has long charged that the Shiite rebels get financial and military support from Iran, an allegation Tehran has denied. Saudi Arabia also accuses Iran of meddling in Yemen's affairs.